salix/print/templates/email/invoice/invoice.js

const Component = require(`${appPath}/core/component`);
const emailHeader = new Component('email-header');
const emailFooter = new Component('email-footer');

module.exports = {
    name: 'invoice',
    async serverPrefetch() {
        this.invoice = await this.fetchInvoice(this.invoiceId);
    },
    methods: {
        fetchInvoice(invoiceId) {
            return this.findOneFromDef('invoice', [invoiceId]);
        },
    },
    components: {
        'email-header': emailHeader.build(),
        'email-footer': emailFooter.build()
    },
    props: {
        invoiceId: {
            type: [Number, String],
            required: true
        }
    }
};